Does anyone know of a Japanese show or childrens book that has a grey bear?

I’m a nanny who went strolling with a toddler and his stuffed animal and I can’t seem to find it. It may have been lost somewhere on the stroll and I would like to get him another, perhaps before his parents find out. I could possibly ask them but I think I’d prefer to buy him another to replace it but I have no idea where to find the exact one. The family is Japanese and I believe I may have seen the bears photo on a Japanese book maybe? It looks like a grey animated bear with a yellow and green overall dress I believe. Any tips would be appreciated.