5 month old Lab

Question
We just got a 5 month old male yellow lab 2 days ago. He has supposedly had obedience training and was housebroken, but I have not had direct communication with his previous owners (who got him when he was 8 weeks old). I have two concerns:  #1) Since we've had him he has had 5 "accidents" in the house, usually after I've walked him (he's never gone to the bathroom on a walk yet, but has gone in the yard). I've never trained a dog, so I'm not sure how to handle it.  #2) He seems to have very low energy for a lab puppy. He doesn't chew on toys, will rarely fetch a ball or anything else, and doesn't play enthusiastically with my children (ages 5 and 7). He also doesn't seem to like to go for walks, he hangs back and seems almost lazy. He is more energetic around other dogs, and seems to like to play with them (we don't have one). He does love attention, but doesn't interact playfully. His behavior doesn't seem to fit with what I've read and experienced with labs. Can you give any advice? Thank you!!!

Answer
Hi Marie,
   I would recommend getting another dog to keep him company and solialize him. If you'd like to wait a while, why don't you visit my website (http://www.happytails.weebly.com) and take a look at our dogs there and decide if you'd like to buy from us. I would also recommend taking him to Petsmart training classes. Not only does it socialize him, but it exercises his obedience as well.