Shih Tsu biting

Question
Please excuse my spelling.   My daughter's male shih tsu is approximately 6 years old and very spoiled.  In the last year, he has bitten her twice on the lip when she went to pick him up.  He did this without warning as he does not growl.  The first time he wasn't feeling well and was treated at the vet for a possible muscle problem.  The second time he appeared fine and after the bite, wanted to be near her.  She is single and this dog means a lot to her.  Is there a reason for this and should she seek out a dog behavior specialist or dog training.  He was bought at the age of 1-1/2 years after a breeder could not breed him, so was with other dogs outside.  He has been a house dog since she has had him.  She also has a problem with him urinating occassionally in the house when he doesn't get what he wants.  Obviously, he is very smart.  Would appreciate your help.  Thank you in advance.

Answer
Hi Linda;
Spoiling them is one thing. Mine are spoiled rotten, but you don't let them get away with bad behavior.
I use time out for punishment. It is about a half hour in the small bathroom, no toys, nothing to do but lie there knowing you are being punished.
My little Lhasa has spent more time in time out, that the other 3 have, put together.
It could have been that she hurt the muscle when she picked him up. My Lhasa hates to have his hair trimmed, and especially the hair arounf his face. I Ad to trim ip, he had toi tilt hishead back to look under his hair, to see, it was so long in front of his face.
He attempted to bite me ( or at least wanted me to think he was going to). I chewed his little but out, and popped his nose lightly a couple of times.
That surprised him, because mommy jusat doesn't hit.
I am 72, been taking care of dogs since I was three years old, and have never been bitten.
Not going to start with that little dictator.LOL
At 6, he can possibly be having some trouble with Arthritis, and they don't show they have pain until it gets really hard for them to walk.
When they get into old age, they get cranky too, just like humans do.
But she can't allow him to bite her, that will only get worse.
Chew him out really harshly, tell him he has been bad and is going to time out, and close him up in a room where he can't play, nothing but contemplate what got him the chewing out and punishment.
If the urinating has just recently started, it could be a problem with bladder control, again, something that sometimes comes with old age.
After that bite, it sounds like he was apologizing.
It could be the way she is picking him up is putting stress on a sore muscle ot jopint.
Charlotte