She tore her puppy in half? :-O Not a bad attempted at a limerick, really. But is this a real puppy we're talking about? This is quite alarming! Hehe, perhaps she could have done something else that made her cry, because that part confused me a little. Also, the second line is a little short - two syllables off to make it flow properly, so perhaps reword it to something like, "She would cry for the entire day". A pretty cute poem, really. Keep writing, you have a lot of potential
One question: why would she cry for the whole day BEFORE she ripped the puppy in half?
It's cute, but it's not long enough or 'meaty' enough to do anything with really. It has a small "doesn't make sense" issue...but the rhyming is cute. But there really isn't anything about it that's memorable. It's a poem that if you published a book of your poems you could stick in the book with the other longer, more deep, more meaty poems and get away with but nothing could really happen to it by itself.
I had a little sister called May,
She would cry for the whole day. - Replace 'whole' with entire
Once her puppy laughed,
She tore it in half, - SHE TORE HER PUPPY IN HALF? WHAT KIND OF SICK SISTER DO YOU HAVE?
And never stopped crying again. - Well, DUH. She murdered a puppy!!
Amusing, but sad. May murdered a friggin PUPPY! OMG! WTF?
It was funny. It had pretty good rythm