I’m scared to leave my dog?

I have a malshi (Maltese and shihtzu mix) and he has really bad separation anxiety. For some reason the day we got him he got really attached to me and every time I leave or anything he cries and barks and freaks out. He lives in our house with 4 other family members and we are going on vacation for 10 days. I’m leaving him with a family that has 4 little kids and I’m just worried he’s going to get himself sick if he misses me. Am I overreacting?