There are one set of twins that were born 87 days apart. One baby  was born on June 1, 2012. The next baby was born on August 26,  2012.
Not until you reach retirement age. Typically that's 65, though many pension plans allow you to start collecting early retirement benefits as early as age 55. If you decide to start receiving benefits before you reach full retirement age, the size of your monthly payout will be less than it would have been if you'd waited. Ask the folks who run your plan to create a simple table showing you how your payments will vary depending on when you start.
So the first step is to go to the Social Security Administration's Web site and find out when youâre entitled to full benefits. For those born between 1943 and 1954, for example, you can start collecting benefits at age 62, but youâll only get 75 percent of what youâd get if you wait until youâre 66. If you wait until 67, you get 108 percent of your monthly benefit. And at age 70, youâll collect 132 percent â the maximum you can get by delaying benefits.