Jessica Pare & Boyfriend Welcome Son

Jessica Pare and her boyfriend, musician John Kastner, have a wonderful case of the baby Blues!

The dad introduced their new tiny tot in a photo he posted on Instagram on Friday.

“Please meet Blues Anthony Pare Kastner,” John captioned the pic of his daughter, Summer Lee, 8, holding her little half-brother.

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This is the first child for the “Mad Men” actress, who announced her pregnancy in October.

Jessica and John began dating in 2012.

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She was previously married to actor Joseph M. Smith, but they split in 2010. John was married once before, as well, to Nicole de Boer, with whom he shares a daughter.

Jessica Pare and boyfriend, John Kastner, welcomed son Blues Anthony in March 2015. The father Instagrammed this photo on March 20, 2015 of his 8-year-old daughter, Summer Lee, from his first marriage holding her new half-brother (Instagram)

Catch Jessica in the final episodes of “Mad Men” when the last season of the hit series returns on April 5 at 10/9c on AMC.

— Paige Feigenbaum