returning to base

Question
in a recent game our 2base runner ran to third it was not a forced out I sent her back to 2nd I did not see, but the oppossing team said she had already touch third and you cannot go back , the second base umpire called the girl safe when she went back to second .  The umpire then changed her mind and said she was out  Can you please advise me the correct rules , no one seems to know. Thanks Tracey  p.s.  this a junior league with teenage umpires

Answer
Hello Tracey

Interesting situation, normally if a runner advances a base safely (that is the goal) they wouldn't go back to the last base.

Here is a situation that should help. Let's say there isn't a force play at any base. Your team has a runner at 2nd and 3rd base. The ball is put into play (live ball). The runner at third stays put however the runner that was at second runs and touches third base. After seeing a runner already on third she turns and runs back to second base. If she isn't tagged on the way back to second she is safe. It doesn't matter if she already touched third. If both runners stayed on third base the runner that came from second would be called out.

From your example I assume third was empty and she touched third but ran back to second because you told her to go back. I'm not aware of any rule that says touching an advancing base exempts you from going back to the previous base. I would say it wasn't a smart play but she would be safe.