No annuity in excess of that fixed in accordance with Sections 9--141, 9--142 and 9--143 shall be granted to a widow described in those sections unless the employee re-enters service before age 65, in which case the annuity for his wife shall be fixed as of the date he attains age 65 while in service, or when he again withdraws, whichever first occurs.
40 ILCS 5/9-145