2 1/2 year old is stuttering in reverse

[AJH84]

My son is 2 ˝ and has a great vocabulary and good, clear enunciation.
However, in the past 2 weeks he has begun to stutter the last syllables or sounds of words. For example, he'll say, “I want to watch-ch-ch this movie-vie,” “I want to give the dogs-gs a treat,” or "I got new shoes-s-s."  
I have a 12 y/o half-sister, and she had the exact same speech problem develop when she was 6 years old in the midst of our mom’s and her father’s (my step-dad) divorce. She struggled with the problem for 5 years. She could hardly say a single word without stuttering the last syllable/sound a few times.
I’m wondering if this is a weird stress-related impediment, because my son’s father and I were living together until last month. I kicked him out of my house because he was emotionally/verbally abusive to me, often in front of our son. Since kicking him out, my son has been wondering where his daddy is (he has not seen our son in 2 weeks, and has only briefly spoken to our son by phone twice).
My son seems happy and adjusted, and I think he's coping well with the issue of his dad no longer being in his daily life. The stuttering is hardly noticeable right now, but I worry that it could worsen, as my sister's problem progressed quickly from very mild to stuttering almost every word.
Should I wait and see if he gets worse or clears up, or should I seek speech therapy or other intervention now?

[Kevin Kennedy, Ph.D.]

This version of stuttering, like other forms, can certainly be exacerbated under conditions of stress. The change in the family is a major event, and your son is conveying his upset about it, wondering where his father is. What have you told him about that? The onset of the symptom, and the fact that is seems to be waning, support the probability that it is associated with developments at home. There is no need yet to confer with a speech/language pathologist but, if the symptom persists, it would be wise to seek such a consult.

[AJH84]

As far as telling my son about the issues of our home life, I've made a huge effort to stay postive about his dad. When his dad left the house, it was quiet and civil, as if he was leaving for work. That was two weeks ago, but a couple days after that, his dad blew up at me over stuff he'd left in my home, he called the cops on me, and our son was in the middle of that situation.
His dad has shown no interest in seeing our son since then, and has only talked to him very briefly on the phone twice in the last 3 days, and that was only because he had to make arrangements with me to get his stuff.
When my son asks where his dad is, I just smile and tell him that Daddy went to get his very own house and that he will get to see his daddy soon. Every day I tell him his dad misses him and loves him very much. He seems just fine with that; he acts very happy and content at home and school. Am I saying the right things and acting the right way for him? Is there anything else I should be doing or telling him?
The stuttering is the only change I've noticed in him. And I probably wouldn't have noticed it if I had not seen my sister experience the same problem so severely for 5 years.
Also, his stuttering is not waning, but rather increasing. The first word I noticed he stuttered was "watch," and it was only that word for a week. But since last week it's been at least one word every other sentence, hence my concern.
Thank you for your helpful input. I will give this some time and see what happens.

[Kevin Kennedy, Ph.D.]

You're doing fine, particularly by trying to be positive about your son's father. I would refrain from telling him that his father misses him or loves him. His father can speak for himself if he comes in touch. And it can ring hollow if a child hears that the parent loves him, misses him, etc. and then is not in touch.