Yellow Lab Puppy dribbling

Question
I have a Yellow Lab Pup he is 18 weeks old and has been doing good in training to use outdoors as the bathroom for the most part, however I noticed the past few days he is dribbling as he walks. Last night twice and today twice am not sure if this is a behavior thing or is it Medical. A friend of mine had bought a pup from the same breeder but the last litter and had to put her down because of a hanging uterus and could not control her urine, Any help would be appreciated. John

Answer
If it is a matter of walking away before he is quite finished, I wouldn't worry about it.  If he is dribbling just as he walks along, see the vet.  It is possible it could be something that could be easily fixed.  

I hope the breeder is not repeating breedings that have produced defective dogs.  That is inexcusable.