Why is my dog suddenly NOT housebroken at night?

[Stario]

My 3 year old Boston Terrier started pooping and peeing in the house - it seems like right after her last heat (about 2 months ago) she started pooping in the house at night instead of going outside like she had been trained - We have another dog but it seems to be just her - our other dog is much larger so we can tell by the size of the poop that it's her...she does not do it during the day - it's just at night..HELP!!!!

[sandram]

she does it at night so that u cant catch her in the act...have u been paying less attention to her?neglecting her? if u have then shes trying to tell u something...u should punish her everytime in order for her to understand that its wrng...if shes not ounished then she probably thinks ur ok with it...