I would be VERY cautious about what grassy areas I let my dogs walk or play on. There could be chemicals and/or pesticides there that could prove fatal for a little dog or a cat. Maybe he got exposed to something on the grass but I would watch him carefully...is he going wee wee ok? keep an eye on that.Is he drinking water ok? If he goes on a pee pad keep an eye on the color of his urine. I also would check with the condo place and see what kind of fertilizer or chemicals they use on their grass. If they say it is pet safe dont believe it! I lost my dear cat to this problem at a former residence at an apartment complex. She died a horrible death and by the time i found out what caused it it was too late! I am sure your baby will be fine but please be careful.