Toddler Backsliding on Potty Training

I would go with the pull ups at night, as suggested, at two they are just not waking up when they need to go.

I raised a 60's baby in Germany and at this time there were only, wash and hang on a line to dry, cloth diapers available.
Needless to say babies were trained as early as possible to use the potty, especially for number two.

I had a double duty highchair with a potty in the seat (turned into a seat with a play-table. Soon after she could sit, I would feed her in her highchair, change the hight chair into a low table with the potty chair attached, pulled her pants down and let her sit and play like this for a while.

Most of the time she would go number one and two shortly after eating. I would then take her off the potty show her, her "creation"... after we both had admired it I, diapered her.
On other times, I observed her and when she started pushing and grunting
I quickly sat her on the potty.

From small on, she was used to the potty and knew what goes in there. I never pressured her, it was just a routine. I did show a little bit of disappointment when she used the diaper. At night I always put a diaper on her until the diaper stayed dry.

I am not saying this is a good approach I just thought it might be interesting to know how Germans of that time potty trained their kids :-)

A two year old is undergoing massive brain changes (for instance all memory is being processed into verbal memory) You can expect that there will be forward and back in development. This is true of all children at all stages of development. Just get the child some pullups and don't make a big deal about it.

There are many physical things that can cause it as well. Normally, when we sleep our system slows down the process of sending fluid to the bladder. In some people that does NOT happen so they have a full bladder at night and when they go into deeper sleep cycles it empties.

Check other people in your family. Often, bed wetting runs in families.

Remember, the child is not doing this on purpose or out of any naughtiness! Be gentle and understanding. A two year old is still basically a baby!

When something like this happens, it is often due to some emotional stress or changes. Because of her age, they cannot process these emotions and therefore regress in a physical way. Don't over react as that will draw more attention to the less desirable act and make sure to use positive reinforcement when she uses the bathroom.