I work on an iOS app using SwiftUI and SwiftData. I added a computed property to one of my models - Parent - that uses relationship - array of Child models - data and I started getting strange problems. Let me start with models: @Model final class Parent { var name: String @Relationship(deleteRule: .cascade, inverse: \Child.parent) var children: [Child]? = [] var streak: Int { // Yes, I know that's not optimal solution for such counter ;) guard let children = children?.sorted(using: SortDescriptor(\.date, order: .reverse)) else { return 0 } var date = Date.now let calendar = Calendar.current for (index, child) in children.enumerated() { if !calendar.isDate(child.date, inSameDayAs: date) { return index } date = calendar.date(byAdding: .day, value: -1, to: date) ?? .now } return children.count } init(name: String) { self.name = name } } @Model final class Child { var date: Date @Relationship(deleteRule: .nullify) var parent: Parent? init(date: Date, parent: Parent) { self.date = date self.parent = parent } } At first everything works as expected. The problem arises once I try to remove one of child from the parent instance. I remove the value from context and save changes without any problems, at least not ones that can be caught by do { } catch. But instead of refreshing UI I get an signal SIGABRT somewhere inside SwiftData internals that points to the line where I'm trying (inside View body) get a child from a Query: struct LastSevenDaysButtons: View { @Environment(\.modelContext) private var modelContext @Query private var children: [Child] private let dates: [Date] private let parent: Parent init(for parent: Parent) { self.parent = parent var lastSevenDays = [Date]() let calendar = Calendar.current let firstDate = calendar.date(byAdding: .day, value: -6, to: calendar.startOfDay(for: .now)) ?? .now var date = firstDate while date <= .now { lastSevenDays.append(date) date = calendar.date(byAdding: .day, value: 1, to: date) ?? .now } dates = lastSevenDays let parentId = parent.persistentModelID _children = Query( filter: #Predicate { $0.parent?.persistentModelID == parentId && $0.date >= firstDate }, sort: [SortDescriptor(\Child.date, order: .reverse)], animation: .default ) } var body: some View { VStack { HStack(alignment: .top) { ForEach(dates, id: \.self) { date in // Here is the last point on stack from my code that I see let child = children.first { $0.date == date } Button { if let child { modelContext.delete(child) } else { modelContext.insert(Child(date: date, parent: parent)) } do { try modelContext.save() } catch { print("Can't save changes for \(parent.name) on \(date.formatted(date: .abbreviated, time: .omitted)): \(error.localizedDescription)") } } label: { Text("\(date.formatted(date: .abbreviated, time: .omitted))") .foregroundStyle(child == nil ? .red : .blue) } } } } } } The LastSevenDaysButtons View is kind of deep in a View hierarchy: RootView -> ParentList -> ParentListItem -> LastSevenDaysButtons However once I move insides of ParentList to RootView application works just fine, although I see and warning: === AttributeGraph: cycle detected through attribute 6912 ===. What could be that I do wrong in here? I believe it must something I'm missing here, but after 2 days of debug, trial and errors, I can't think clearly anymore. Here is the minimal repro I managed to create: Signal SIGABRT on accessing values from SwiftData query