For four years until the end of 2011, retiree Liew Su Liong and his wife travelled to Sydney, Australia, for three-month stints twice a year to care for their granddaughter Claire, now seven.
The other set of grandparents formed the other half of the tag team, shuttling to Australia from Singapore for similar three-month stints.
Claire was cared for by both sets of grandparents from infancy to about four years old because Mummy - Mr Liew's daughter, Wen Dee - was studying at the time.
Mr Liew, 69, says it "seemed like a natural thing to do" for him and his wife, Madam Yong Soon Fah, also 69.
"Wen Dee wanted to do an occupational therapy course. We wanted to help her accomplish it. We could be sitting in Singapore but we wanted to see the kids. It was a little bit of sacrifice," he says.
His 36-year-old daughter emigrated to Australia about eight years ago with her marketing executive husband. They now have a younger daughter, Zoe, aged 19 months.
Ms Liew, now a stay-at-home mum, says: "It was a good chance for my kids to get to know their grandparents. We were new to Sydney and we didn't want Claire to start in childcare so young.
"I find it especially nice because, unlike Claire, I grew up away from my grandparents, who lived in Miri in Sarawak.
"Claire has that bond with her grandparents that Zoe doesn't have, though we can build that up over time."
Other grandparents resort to technology to keep in touch with their grandchildren living in a different country.
Mr Martin Koh's three grandchildren in Chicago take turns every weekday to talk to with him and his wife Maggie, via an iPad in the car on the way to school.
Mr and Mrs Koh, retirees who live in Singapore, usually talk to 12-year-old twins Daniel and Ryan, and their sister Lara, five, on FaceTime, the tablet's video-chat application.
The Kohs' daughter Debra, 40, a stay-home mum, and her family have lived in the United States for more than seven years.
Despite the 14-hour time difference, keeping in touch "as good as 24/7" is a cinch with social media and mobile apps, says Mr Koh, 71, who retired from marketing chemicals at Exxon in 2002.
The minutiae of everyday life is shared in WhatsApp photos - a light bruise on Lara's face when a classmate bumped into her, or Debra sending a picture of shoes on sale that her mother may like. Either side visits the other at least once a year.
Mr Koh says: "It's very convenient, just pick up the iPad, press one button and we're talking. It's for 10 to 15 minutes to say hello. When they don't call, sometimes we are quite concerned. It's a blessing that we can talk to our grandchildren every day."
Experts say that seeing one's grandchildren onscreen, as opposed to using the telephone, can strengthen the bond.
Ms Soh Swee Ping, the chief executive officer of Council for Third Age, a non- profit organisation that promotes active ageing, says: "It creates emotional wellness when grandchildren and grandparents see each other on the screen. You don't just want to hear their voice, you really want to hear more from them and see how they're doing."
While being in the same physical space is "a different kind of happiness", she adds that in inter-generational, long-distance relationships, "grandparents can become like a friend and it's not just babysitting".
The Kohs have a son, daughter-in-law and another grandchild, 17-month-old Sarah, living with them here.
While they see "no difference" between their bond with Sarah and their US-based grandchildren whom they are in constant touch with, there is no substitute for actual face time.
"At times, we feel we would have loved to be there for events such as birthdays, Christmas and class graduation," says Mr Koh.
"My daughter makes up for it by sending us videos of activities, including their concert performances. It alleviates our feeling of lack. We are participating but afterward."
Sociologist Paulin Tay Straughan, whose research interests include ageing issues, says "transnational families is the way it's going to be".
She adds: "Singapore being so small, there's always this possibility that you may have to move overseas to find meaningful employment."
But within limitations, being faraway and yet so close can help one another appreciate the time spent together.
Another long-distance grandparent, housewife Judy Tan, who is in her 60s, uses FaceTime to let her two-year-old grandson, Luke, view and say hello to her pets - a tortoise, arowana fish and two Alaskan Klee Kai dogs, which resemble huskies.
She and her husband Clarence Tan, 74, a retired military man, have a daughter Marjorie, who is in her early 40s and works in San Francisco for the Ministry of Foreign Affairs. Besides Luke, their other grandchild is Emma, seven.
Mrs Tan says: "Sometimes the separation enhances the quality of the relationship with our grandchildren and children, as long as the bonding is there. When you physically meet during visits, you find the time more precious."
But Mrs Evelin Pereira, 75, is among the seniors who are less wired. Widowed about seven years ago, she uses a pre-paid mobile phone, mostly to receive calls.
For the past five years following a gall bladder operation, the retired factory worker has not been able to take a flight to Ireland, where her younger daughter Pamela, 55, lives with her Irish computer engineer husband and their four children, aged between 14 and 21.
Mrs Pereira says she sees her grandchildren once every two or three years, when they visit Singapore.
Her elder daughter, who is not married, works as a nurse in Newcastle in Australia.
Mrs Pereira mostly keeps in touch with her grandchildren via telephone calls - she has caller ID and a long-distance phone card. Recently, the tenant who rents a room from her helped her to see her grandchildren on the computer screen for the first time in years, using Yahoo Messenger.
Mrs Pereira recalls how she felt "very miserable" when the grandchildren left for Ireland around 1998. She took up a full-time night shift at the factory she worked at then, to assuage the ache and "not think about it".
"I came home after working from 7pm to 7am, did my housework and went to sleep. My daughter had left for another country, what could I do?
"At the time they left, the grandchildren were small and very cute and so close to me. I felt so sad. Now, I also feel sad whenever I think about that time.
"When my husband died, they all came to Singapore. When they left, I felt miserable, being all alone here."
This article was first published on Feb 1, 2015.
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