Jiéhūn hòu, tā kāishǐ gǎikǒu jiào gōngpó bàba māma.
After getting married, she started calling her parents-in-law mom and dad.
Tips
usage
改口 has two distinct uses: (1) retracting or revising something said, and (2) changing how you address someone, especially when a new family relationship forms after marriage.