If Wally marries Jesse, earth 2 Doctor wells will become the father-in-law of Wally and the co-father-in-law of Joe and Francine (that's how we call the parent of a child-in-law) and Jesse will become the sister-in-law of Iris, the half-sister-in-law of Jenna, the co-sister-in-law of Barry, the daughter-in-law of Joe and Francine, the great-granddaughter-in-law of Esther, the stepdaughter-in-law of Cecile (if Joe marries Cecile), the stepniece-in-law of Cecile's sister (if Joe marries Cecile), the stepgreat-granddaughter-in-law of Millie (if Joe marries Cecile) and the stepsister-in-law of Joanie (if Joe marries Cecile)