“Don’t worry,” Derick, 26, joked in the caption. “We won’t be doing these weekly photos until he’s 18.”
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The 19 Kids and Counting star just celebrated her very first Mother’s Day, telling PEOPLE, “It is so crazy that last Mother’s Day, I wasn’t even married, and now I’m a mom. It is still surreal to me that I’m a mother.”
Added Jill, 23, “I am so blessed to be a mother. There are a lot of ladies who would love to be and can’t. My heroes are my mom, my grandmother, Derick’s mom and those people who have been mothers for a while. I just pray I can be like them.”
The two-hour finale of 19 Kids and Counting airs Tuesday at 8 p.m. ET on TLC.
Want more Duggars? Click here to get weekly updates on the stars of TLC’s 19 Kids and Counting in the Duggar Family Newsletter.