Eyebrows raised as older men father children.(Knight Ridder Newspapers)

At age 67, San Francisco Mayor Willie Brown became a dad once again last month. At 69, U.S. Rep. Pete Stark, D-Calif., announced that his wife is expecting twins in August.

Not everyone is offering congratulations.

Older men fathering children is nothing new. The Bible even promotes fatherhood at an advanced age. Yet each new example _ whether it's the recent political papas or celebrities such as Tony Randall or Clint Eastwood _ continues to arch eyebrows, generate cubicle chatter and unleash a flood of impassioned calls to talk radio.

"This cuts deep into a lot of issues many Americans don't feel comfortable talking, or even thinking, about," said Jerrold Lee Shapiro, a psychology professor at Santa Clara University who has written three books about fatherhood.

The prospect of an older man with a son or daughter that could well be his grandchild or great-grandchild touches on sensitive issues such as sex, arrogance, trophy wives and death. It rattles the sense of what is proper and expected at each stage of life.

But many psychologists say there are trade-offs to having children at any age. A young father may have more stamina, for example, but he may also be more distracted by trying to make his name in his profession. An older father may have less energy, but he may be more patient and financially stable. If he neglected his children the first time around, maybe he won't want to make the same mistake.

"Is it better for a child to have an older, loving, caring, present father for a shorter amount of time, or a father in his 20s who is working 65 to 75 hours in a Silicon Valley week?" Shapiro asked.