This morning I took my 17-month-old son Marco to the playground, where he loves to go down the slide, head-first. He went through the usual routine: climb the stairs, go down the slide, laugh out loud, repeat. At some point he surprisingly pointed at the swings. We rarely go to the swings now; I’m guessing he lost interest in them after he started enjoying the adrenaline rush of the slide. So we went to the swing, and we laughed and cheered at each oscillation. READ MORE: The Fatherly Guide to Stay-At-Home Parenting Three months ago I started a new life: I quit my job as a Product Manager at HotelTonight to become a full time dad. At the time I was working an insane number of hours and I ended up seeing Marco less than an hour per day. He was starting to say his first words, take his first steps, go through all these incredible development milestones, and I was missing all of that. During the day I kept receiving pictures of Marco from my wife and, rather than making me happy, they made me mad. I had been at HotelTonight just about 7 months, and it was the best job a Product Manager could dream of: shipping lots of good stuff, very fast. Without rewriting most of the same, the reasons for my change were identical to Juney Ham leaving AirBnB, except I was not leaving a unicorn so my decision was eons of times easier to make. While Marco was happily swinging, I grabbed my phone and recorded a video. Unfortunately now when he sees my phone he wants to play with it, rather than pose for me. First he yelled at the camera and eventually looked away, which made for a pretty lame video. Right next to us, in the swing to my left, was a 9-month-old baby girl. Her mom was pushing her gently. I suddenly remembered that I had taken a similar video of Marco in that same swing when he was younger, so I started browsing through my phone searching for it. When I started this parenting gig 3 months ago, it was really hard not to be naive: all the thoughts that came to mind were about strong bonding and unlimited happiness. However, the left side of my brain reminded me that we were about to cut our monthly income by half, while our mortgage was not going to change and our health insurance payments would increase dramatically. I knew this was not a sustainable choice but I told myself it would only be temporary: 3 months? Six months? Nine months? At some point the kid will go to some type of school anyways, right? How long is my new life going to last? I remember thinking “I should start a spreadsheet and put the numbers down to estimate the runway.” After much scrolling, I found the video. I hit play and I gasped. In the video, Marco was a tiny creature in the swing bucket, essentially bald, wearing a one-piece pajama and smiling like a… baby. Then I looked at the toddler Marco in front of me, a tight fit in the same swing, with messy hair, wearing vintage blue jeans and a pair of Converse All Stars. Gazing at 2 black crows flying in the sky with an inquisitive look. I never started the spreadsheet. The idea of dedicating my whole self to Marco won over the financial concerns. An instinct driven by unconditional love? Most likely. However, deep inside I knew we could run our operations with one salary for a little while — something we are extremely fortunate to be able to do. We canceled Netflix and Spotify, and of course scratched plans to buy a new car; our 1998 VW has seen better days, but it runs just fine. And anyways, one major thing that a spreadsheet would not be able to calculate is how fast time goes by. My little man is growing too fast and I know that my new life is already about to end, too soon. Peppe Ragusa is a writer. Check him out on twitter, and find more of his writing on Medium.