The pair have marked their first Valentine's Day as a married couple by announcing that they're set to welcome a little bundle of joy into the world in a few months' time.
The 43-year-old screenwriter shared a photograph of him and Tom nestled up to one another while holding a scan of their baby out in front of them.
He accompanied it with the caption: ''A very happy #ValentinesDay from ours to yours. (sic)''
The 23-year-old Olympic diver then shared his own version of the picture - this time with him and his husband looking at the camera - on his social networking sites.
He simply wrote: ''HAPPY VALENTINES DAY (sic).''
Their happy news comes just six months after Tom said he and Lance were keen to start a family together - but he couldn't pinpoint at the time when they would start trying.
He said: ''Lance and I definitely want a family in the future - who knows when? We're both lucky to have supportive families and we want to share that with our own children.''
The couple - who now live together in London - got married in May last year at Bovey Castle in Devon and they previously admitted it was love at first sight when they were introduced to one another back in 2013.
Speaking in their wedding video, Tom said: ''Within the first few minutes of conversation with Lance, things suddenly and massively changed for me. I fell in love. Every single part of him, the way he thinks, the way he acts and everything that he does just makes me fall in love with him every single day more and more.''
Dustin added: ''When Tom and I met four years ago, I knew instantly that I was in trouble.
''I knew I'd met my match. I'd met someone who could inspire me, someone who I could admire but also somebody who would naturally be my best friend.
''It didn't hurt that he was incredibly cute and charismatic and didn't let me get away with a thing.
''It just seems that he and I have been able to overcome every single challenge of distance and time apart and it just brings us closer and closer together.''
From 'Happy' to 'Banana Pancakes', these are soaked in positivity.