GARLAND, Texas -- A Texas teenager got a real-life biology lesson when his baby brother decided to arrive earlier than expected.

Angela Howard had just taken a bath when she quickly went into labor.  Her 15-year-old son, Dameyon Howard, called 9-1-1 but the baby was not waiting for EMT's to arrive.

Dameyon used a shoelace string to sever  the umbilical cord.

"You know I had to get my breath. It was just like mind-blowing," said Dameyon.

When paramedics got to the apartment they said everyone was calm.

The baby born 10 days early is healthy and already owes a big debt to his older brother.