may i recommend lai chi kok park on 29 may afternoon say 330 or 4 pm?
it's a huge park, has some chinese pavilions/good for taking photos, large grassy areas, can watch the xtreme skateboarders in that particular area if you're into that type of thing. and there's many playgrounds for children so it's not usually crowded, there's also a stage/tented area where we can lay out a mat for the non-walking babies if we want to stay out of the sun...