My youngest sim's inventory keeps getting moved to his dad's inventory

I have a male human sim and he has 5 alien kids. All the kids and the dad have items in their inventory. I put a wabbit tablet into the youngest's inventory along with some photos i took of the family (i put family photos in all of their inventories). But as i was sorting which photo each member had already, i went back to the youngest and his entire in inventory was gone. I looked in the other sims's  inventories first and found the dad head then in his. No matter what i put in the youngest's inventory it always goes to the dad's inventory. The kid isn't gifting his dad anything (the kid's a toddler) but it's only the toddler that's effected. I put stuff in the toddler's inventory and when i select another sim for a bit, then go back to the toddler, the toddler's has been added to his dad's.