Dynamics 365 is a wonderful tool and many of the configurations are just as great. There is one configuration in particular that occurs out-of-the-box that can be changed improved in all implementations: the parental relationship between Accounts/Contacts and their child records.
For example, when you change the owner of an Account, the default behavior will be to also change the owner of all activities, including completed tasks, emails and phone calls. This is usually not the desired behavior as you want to see who originally completed the activity. Let's walk through how to change this behavior for the Account and Phone Call relationship, and these steps can be followed for most Parent-Child relationships in Dynamics 365.
1.)Navigate to the module drop down selector and click Settings.
2.)Click Customize the System.
3.)Expand Entities and expand Account.
4.)Click on 1:N Relationships.
Optional: I click on the Related Entity column to sort by it so it's easier to find the correct relationship.
5.)Find the Account to Phone Call relationship and double click to open it.

6.)In the Relationship window, find the Type of Behavior field, which is currently set to Parental.
7.)Change this option to Configurable Cascading. You will now notice that the fields below it are also available for editing.

8.)We recommend changing the Assign option to either Cascade None (as shown above) or to Cascade Active.
9.)Cascade None- no Phone Calls would be reassigned when the Account is reassigned.
10.)Cascade Active- only Phone Calls that are Active at the time of assignment would be reassigned to the new Owner. This option may be helpful if you are reassigning Accounts due to someone leaving the company.
Another item to note: if you have any workflows that trigger on Assign of records, such as Leads, Opportunities or Cases, you will want to update those relationships as well. For example, if an email is sent when a Case is assigned to a user, you will want to modify the Account to Case relationship with the above steps.
11.)After changing this, you can click Save and Close, and then Publish. If you are going to update this for multiple activity types at once, we would recommend to click Publish All Customizations once you have completed all your modifications.
To learn more, check out this blog: How to Increase the Number of Child Cases a Parent Case Can Have
Happy CRM'ing!
Do you know in which case it would be useful to leave this as is? What is the reason the system is set up like this by default?
Many thanks, the article helped me!
Thank you! Big help.
We have assigned the owner of a parent account to a different person and owner of all child accounts and related cases changed to new assigned owner.
is there any way to revert back the changes?
If you have cascade active that should only affect the OWNER field not the CreatedBy, right? When User A (internet sales rep) creates an open appointment and puts User B (onsite sales person) as the owner we're noticing when User B completes the appointment it's actually overwriting the CREATEDBY field to User B. Our internet reps (user A) are losing commissions because they no longer are showing as having generated the appointment.