Clingy 18m

My 18m is heading to PG in few months time. Im currently pregnant with number 2. My 18m is so clingy that she clings to me all the time, even though i have a helper. She will refuse my helper everytime and run to me, rejecting my helper. But yet at the same time she plays with my helper. Is this a concern whereby i should be worried about my helper or its normal that they find and prefer their mum even though i spent most time working? Kindly advice pls. Thank you