Most young kids go through a stuttering phase. 99% of them grow out of it relatively soon. My 3 year old son has autism and repeats a word over and over sometimes. But difference is he’s just repeating it, he’s not stuttering. When he sings his bedtime song with me, he will sometimes repeat the word ‘ Night’ again and again, but with enthusiasm. He likes the word! If it continues for a while, I’d see a specialist, but for now just keep an eye on it. It’s too soon to say for sure what it is.