Levi Johnston and Bristol Palin (right)
Landov, Balkis Press/Abaca
Levi Johnston, the boyfriend of Sarah Palin's 17-year-old pregnant daughter Bristol, is going to join the Palin family at the Republican National Convention, according to his mother.
Sherry Johnston told reporters that Levi left Alaska on Tuesday to fly to St. Paul, Minn., according to the Associated Press.
GOP vice presidential candidate Palin announced Monday that her daughter is five months pregnant
and plans to marry the baby's 18-year-old father.
Asked to respond to reports that the young couple had been pressured to marry, Sherry Johnston replied, "Absolutely not." She said that Levi and Bristol (who wore what appeared to be an engagement ring to an Aug. 29 PEOPLE photo shoot) had plans to marry even before they learned that Bristol was pregnant.
Like Bristol, Johnston was raised in Wasilla, Alaska, where he was a star forward for his high school hockey team, the Wasilla Warriors. Despite an injury last season, he played the final game in February.
"He's a good guy," a Palin relative told PEOPLE. "They'll be good together."
According to Johnston’s MySpace page (no longer accessible on the site), he likes to ride dirt bikes and enjoys camping and fishing. An Alaskan newspaper reported that Johnston and three friends narrowly escaped harm in a mountain avalanche while snowboarding last winter.
The Palin relative said the couple's romance and pregnancy was not a secret among family members in Wasilla. "They kind of let everyone know [last May] and word traveled quick," the relative says. "We were surprised, but everyone is positive."
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