The 40-year-old took to Instagram Tuesday after welcoming a baby boy, Hayes Jennings, with his wife and "The Bachelor" alum Peyton Wright Lambton on Sunday.
Lambton shared a slideshow of photos of his family with their new addition. He and Peyton are also parents to 2-year-old daughter Lyla James.
"And now there's four!!!! So happy to have another member of our family. Little #HayesJennings was born Sunday and both he and @peytonwlambton are doing great #merrychristmasbaby #familyof4 #sohappy," the star wrote.
Peyton posted a series of pictures on her own account.
"IT'S A BOY!!! Hayes Jennings Lambton arrived Sunday morning and we are so in love! #babyboy #familyof4 #newborn #pregnancy #birth #family #hayesjennings #lylajames #bigsister #littlebrother #somuchlove #christmasbaby #happytobehome," she captioned the post.
Lambton and Peyton announced in July they were expecting a second child.
The couple conceived naturally after experiencing a miscarriage and using in vitro fertilization to have Lyla.
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"As I was waiting to start my cycle in April I found out I was pregnant! Yes, naturally!" Peyton said in a blog post.
"We can't wait to see Lyla James as a big sister. She is so nurturing and loves taking care of her baby dolls so I think and hope that will transfer into a real baby. Fingers crossed!" she added.
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