His family used to take him on overseas trips to far-flung destinations such as Europe and the United States, but they gradually noticed changes in retiree Chan Sen Hwa.
Mr Chan, 80, was diagnosed with Alzheimer's disease about three years ago during a check-up where he underwent several brain tests.
Mr Chan's daughter-in-law, housewife Stephanie Chan, 43, said: "It was very sad to see him change. He is more like a father than a father-in-law to me.
"When the family moved to China for five years from 2003, he came to live with us and we would cook together. We were very close," she said.
"Now, he doesn't like to go out that often anymore and he keeps to himself."
A frequent visitor to the Singapore Zoo, Mrs Chan managed to convince her father-in-law to go there on a family outing two years ago, and that particular outing remains her fondest memory there.
This prompted her to submit photos of that outing to #MyMandai, an ongoing online photo-sharing event commemorating moments that matter at Singapore's wildlife parks. (See report, above.)
"It was a good chance to get him out of the house because his mind would be more active when he does things," said Mrs Chan, a Singapore permanent resident from Malaysia.
"When we brought him to the Singapore Zoo, we could all tell how happy he was. He fed the giraffes and the white rhinoceros, and sat on the elephants."
Mrs Chan's third son, Adrian, 13, said: "It's very rare to see him that happy because usually, his mood swings. But on that day, he was overwhelmed with happiness."
Mr Chan said: "I was very impressed with the variety of animals at the Singapore Zoo and it was an exciting experience as I could go up close to the animals to feed them.
"If there's another occasion to visit the zoo, I will go again."
Miss Bhargavi Sekar had also sent in her childhood picture to #MyMandai and still fondly remembers how thrilled she was when a chimpanzee put its arm around her while posing for a picture on her first visit to the Singapore Zoo when she was six.
But her childhood dream of becoming a zookeeper was crushed when she found out she was allergic to animals, which causes her to sneeze, have sore throats and irritated skin.
Through an operation for tonsillitis when she was 11, her doctor told her there were 48 things, including dust and fur, which she had to avoid.
The 23-year-old, who is looking for a job, said: "I was very sad, knowing that I wouldn't be able to spend a lot of time with animals."
But her experience at the Singapore Zoo helped develop her love for animals, and her favourite animal is the giraffe.
"I don't remember watching Cartoon Network when I was a kid, but I remember watching Animal Planet, even though I didn't understand anything back then," said Miss Bhargavi, a Singapore permanent resident from India.
"I feel that animals set very good examples for how humans should be, and we've so much to learn from them just through observation."
She has not allowed her allergy to stand in the way and volunteers at the Society For The Prevention Of Cruelty To Animals, on top of applying for jobs in the Singapore Zoo.
Miss Bhargavi's mother, housewife Vasantha Sekar, 48, said: "Bhargavi can do whatever she wants as long as she likes the job. "She has loved animals since the first time we took her to a zoo in Bangalore when she was about three years old. Even now, she still enjoys visiting the zoo, and has been there at least 10 times already."
Miss Bhargavi said: "The Singapore Zoo always keeps things interesting and there is always a new show or a new exhibit every now and then.
"I'll always be there even before the zoo opens, and I'll stay there till it closes whenever I visit because there's just so much to experience."
This article was first published on Feb 1, 2016.
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