Serena seeks parenting tips, says 'nothing is working'

American tennis player Serena Williams took to Twitter to ask for help in dealing with her three-month-old daughter's teething problems. "Nothing is working. It's breaking my heart. I almost need my mom to come and hold me to sleep cause I'm so stressed. Help? Anyone??" wrote Serena in one of her tweets. Serena gave birth to Alexis Olympia in September.