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Jen Arnold has shared a photo of her during her treatment to fight cancer. The star of "The Little Couple", who announced recently that she was diagnosed with a rare form of cancer, has started her chemo treatment as an inpatient and she lost her hair as the result.

"Day2 inpatient chemo- sleeping a lot, liking new anti nausea med this time, & looking to get home today! #GetWellJen," wrote the neonatologist and a mom of two on Twitter. In a photo she attached on the post, Arnold can be seen smiling as she takes the selfie. Medical equipment makes appearance in the background.

The reality star previously postponed the treatment for a week because of low blood counts, but she told followers on Twitter that the "silver lining" was that she was able to have "a better Xmas" with her husband and their two children. Arnold spent the holidays baking cookies with 3-year-old Will and 2-year-old Zoey while her husband Bill Klein prepared Italian food.

She also said that her father a.k.a. Santa would come for the holiday celebration. "Can't wait to see the kids reactions!" she wrote, adding a photo of Will and the Santa the next day. Arnold also uploaded a photo of her son playing with his toy. "Will wishes everyone a happy, peaceful, and karaoke filled Christmas!" she captioned the photo.

After adopting Zoey, Arnold announced earlier this month that she suffered from a rare type of cancer. "I am very fortunate as the prognosis is good. While there is never a good time to get news like this, getting it just as we are building our new family is tough in many ways," she said in a statement to PEOPLE.

Merry Christmas everyone! @ReallyBillKlein @judy_arnold #LittleCouple @tlcontlc pic.twitter.com/YdbHILg5Gj

— Jennifer Arnold, MD (@JenArnoldMD) December 24, 2013