Not much to go on here, but sounds like your daughter died? Rights of survivorship vary by state, but in most states property with right of survivorship automatically passes to the survivor when one of the owners dies.
There is no mortgage to "assume" since you were already are on the mortgage. Check with your county register of deeds, as you will need to file documents showing you are the sole owner.
I'm only speaking from experience in Michigan, so not sure how it is in your state.