The 33-year-old Season 17 star and Giudici marked the fourth anniversary of their engagement by sharing sweet posts on Instagram.
"4 years ago today, I locked down this hottie for life and followed it with a sweaty makeout session. Aww young love," Lowe captioned a photo of himself kissing Giudici after his proposal.
"I love this man I love this man I love this man I love this man #fouryearstogether," Giudici added to a picture on her own account.
Lowe and Giudici got engaged on "The Bachelor" Season 17 finale, which aired in March 2013.
The couple married in Santa Barbara, Calif., in January 2014, and welcomed son Samuel Thomas in July.
"Parenthood is going to be an amazing process. It will be what we want it to be and we can't wait," Giudici told Parents magazine prior to her son's birth.
"She'll be an unbelievable mom. I've never met anyone that loves as hard as she does. When she puts her heart into something, she puts everything into it. I know that will transition to our child and it will be so cool to watch her take that motherly role," Lowe gushed.
Lowe and Giudici have also appeared on "Celebrity Family Feud," "Celebrity Wife Swap," "Marriage Boot Camp" and "Who Wants to Be a Millionaire."
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