Bella Santorum celebrated her fourth birthday on Mother’s Day, May 13.

Her father, former presidential candidate Rick Santorum, and her mother, Karen, wrote the following to the former campaign supporters about her: “Bella is a ray of sunshine at the center of our family’s universe, every day inspiring our family with her joyful spirit.”

They invited people to submit birthday wishes to Bella via the website and on Twitter with the hashtag #happybirthdaybella.

Incidentally, Isabella was the No. 2 baby girl name in 2011, according to the Social Security Administration’s 2011 top baby-names list released May 14.

Isabella was the top girl’s name for the previous two years. Sophia was No. 1 in 2011, with Emma, Olivia and Ava rounding out the top five.

Jacob was the top boy’s name the 13th year in a row. Mason rose 10 spots to become the second-most popular name. William, Jayden and Noah were the rest of the top 5. Michael came in sixth, the name’s lowest ranking since 1948.

The Social Security Administration provides lists of baby names dating to 1880 on its website, That year the top names were John and Mary.