The Little Couple's Dr. Jen Arnold is going back to work after leaving late last year to wage her valiant battle against cancer.

“Tomorrow is a big day for me- first day working back in #NICU @TexasChildrens! #backinthesaddle,” the doctor, 39, tweeted Monday.

Arnold, who is cancer-free and in remission since undergoing chemotherapy, had been battling a rare strain of uterine cancer called choriocarcinoma.