Short answer is that there are duplicate profiles for the children (at least for Charles), too.
If you open the 2 links for Charles, you should notice that the profiles have different WikiTree IDs (Denning-157 and Denning-396). These are probably duplicates and should be merged. Or there may be incorrect data related to some profiles, so follow the advice in the next paragraph before trying to correct anything!
I noticed that Denning-157 is also linked to James as his brother; James is also linked as his own brother! I suggest you first make yourself a hand-drawn chart to verify all the family links before you proceed with any corrections.
If you need additional help, just post again!