User is comprised of the following:

    email: {
        type: String,
        required: true,
        unique: true,
    },
    hashedPassword: {
        type: String,
        required: true,
    },
    token: String,

Pet is comprised of the following:

    name: {
        type: String,
        required: true
    },
    type: {
        type: String,
        required: true,
    },
    age: {
        type: Number,
        required: true,
    },
    adoptable: {
        type: Boolean,
        required: true,
        default: false,
    },
    toys: [toySchema],
    owner: {
        type: mongoose.Schema.Types.ObjectId,
        ref: 'User,
    }

Toy is comprised of the following:

    name: {
        type: String,
        required: true
    },
    description: {
        type: String
    },
    isSqueaky: {
        type: Boolean,
        required: true,
        default: false,
    },
    condition: {
        type: String,
        enum: ['new', 'used', 'disgusting'],
        default: 'new',
    }