Mudsy grew up in a mansion called Muddlemore Manor with his family. When he was an adult, he joined the war with his pet cat, Boo.
One day while picking flowers, he and Boo saw some redcoats attacking and burying a treasure. When the redcoats chased after them, they hid in a grandfather clock in some old mansion. Unfortunetly, they couldn't get out and suffocated in it. Centuries later, they were released from their chiming prison
Mudsy is a huge coward and is afraid of everything he and the kids come into contact with (such as modern-day elements and the monsters and bad guys), possibly due to being traumatized from war violence. However, Mudsy has his moments of bravery and always ends up saving the day and capturing the bad guys. He also loves April, Skip and Augie as if they were his own children, and acts as a father-figure to Boo and the kids.