Adjust Form If Child Table Has A Record With Current Date

I have been searching and searching and cannot find my answer. I am hoping someone can help. 

I have a table to track who has RSVP'd for an event related to another table tracking the events to RSVP to (Date, event name, cost, and link are the fields). I have the relationship as one event to many RSVP's. Here is my dilemma:

I want the form for the RSVP's to display particular sections I have, depending on whether or not the event table has one or more records with the date field having the current date. I was thinking I needed to establish another relationship with the events related to itself, so I could use a summary field to get a count of records with the current date. Unfortunately, my summary fields always end up blank so, I am not understanding summary fields completely and/or, I cannot do what I want the way I want. I considered maybe using a formula field with, perhaps, an API_DoQueryCount call or something but, trying to figure that out has been even further beyond my understanding. 

Any suggestions on approach, links to explanations for how summary fields and/or using API calls in formulas would be greatly appreciated. Please do not direct me to QuickBase's help guides. I have read and read their info and, while I am future along with the overall development of the app, I am still stuck with this dilemma. Thank any and everyone who chimes in for attempts to assist in advance for your time.

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James Carr
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