The collectibles are meant to be a reward for playing, so your family members will not collect them unless the player directly puts them onto the collectible every time. Duplicate collectibles are automatically sold, and new ones are automatically added to the collectibles cabinet.

The over-praising can relate to praising a family member more than twice in a row. The person being praised will run away, but there are ways to repeat the cycle. Experiments are fun!

Over-correcting (via the scolding glove) has the possibility of making the family member depressed, so that is something to keep in mind. I hope this helps!