In the photo Brolin stood shirtless wearing dark-colored cargo pants while pointing at his leg which had dark splash marks on it reports people.com.
"Stoked about pissing all over myself again " Brolin wrote in the caption.
"One of the great gifts about turning 50 is the sudden biological changing out of your shower head. What used to be a rush of garden hose now seems to have morphed into a multi-directional sprinkler. Just want to let everyone know what there is to look forward to - those who haven t reached this incredibly illuminating milestone " he added.
The "Deadpool 2" actor turned 50 in February and is expecting his baby girl with wife and model Kathryn Boyd.
Brolin is already a father to two adult children -- 30-year-old son Trevor and 24-year-old daughter Eden -- from a previous relationship.
--IANS nv/rb
