We travelled for 90 days between July and Oct 2018. Then Hawaii Dec 2018. Can we come back to the States June to Sep 2019?
The Visa Waiver Program allows ESTA holders to enter the US for tourism for up to 90 days per visit. There is no specific time period that you must stay out of the country, or any specific ratio of time spent inside vs outside.
Having said that, the immigration officer will make a determination when you present yourself at the border, whether to admit you under the VWP. They are not under any obligation to admit you just because you hold an ESTA, and they may refuse entry for any reason.
With your travel history, it doesn't seem like you would be trying to live within the US through frequent visits, so I don't see any reason why you would be refused entry. There are never any guarantees, of course.