with friends mom?

hi all i was having a pretty boring summer so i decided to do odd chores for my neighbors and and friends and so once i decided to do some gardening for a female friend of mine; she had gone out with her other friends [and i was hoping we could do it together] and so i was feeling pretty resentful but after a while her mom came out to sunbathe....after some little talk things got intense and then you know the rest.....now i told her it was a one time thing but i would love to carry things further....what do you guys think? and she said that she will never tell her daughter but in the movies the moms always snitch; do u guys think i should just tell her meself and make it sound like she seduced me or just keep quiet?