Birthdays always feel like big milestones, but there's something about the transition from your 30s to 40 that feels especially major. The big 4-0 can make you feel both older and wiser.

I celebrated my 40th birthday by going to Las Vegas with friends and was nervous it'd be exhausting. Instead of partying like I was 21, I embraced a relaxing trip with activities I was excited about.

Actor Kushal Tandon celebrates his 40th birthday, receiving heartfelt messages, including a notable one from actress Shivangi ...